基于用地效率分析的城市区域空间结构极化模型及空间发展战略

不同规模的城市其用地效率具有一定的差异性.本文通过对中国660余个不同规模城市的用地效率分析,在总结和分析了传统城市区域空间结构基本理论和模型的基础上,提出基于城市用地效率分析的城市区域空间结构极化模型.通过理论与实证分析表明,城市发展的方向一极是大型化,发展成为特大城市或超大城市(人口100万-400万);另一极是小...     

基于区域经济差异和协调发展理论的城市旅游圈竞合发展研究——以广西北部湾经济区城市为例

随着广西北部湾经济区的发展,区域内城市旅游圈的合作也需要不断深入.文章通过对城市旅游圈合作发展的理论诱因和现实条件分析,初步探讨了广西北部湾经济区城市旅游圈的旅游合作的动力机制,提出加强旅游资源整合、空间连接、区域形象、市场拓展和制度保障等整合与协作,促进整个地区城市旅游圈的协调发展.     

城市空间的生产方法论探析

“空间的生产”是新马克思主义城市学派的核心概念.哈维在发扬“空间的生产”理论并将其用于城市问题研究上具有代表性.其城市空间分析的方法论特点有三:立足于自身问题;自由和富有批判性;阶级分析和文艺分析相结合.国内案例研究反映出微观与宏观、时间与空间尺度结合的重要性.     

Relationship between city size and firm productivity – A new interpretation using the Chinese experience

This paper contributes to the literature on the relationship between city size and firm productivity by focusing on agglomeration, selection (market competition), and sorting (presence of firms with diverse productivity) effects using Chinese firm-level data for 1998–2013. Contrary to the existing literature, our parametric regression estimates from nearly two million firms show that when the selection effect is controlled, productivity advantage in big cities is reversed. This outcome is explained through a quantile regression showing the existence of left-sided sorting (inefficient firms sort themselves to larger cities) in big cities which is not captured in existing empirical literature. We further find that (1) left-sided sorting is stronger in exporters than non-exporters; (2) is also generated mainly in enterprises with high asset-liability ratios; and (3) selection has a positive effect on firm productivity, suggesting that market competition is key in an explanation of the rapid growth of big cities in China.     

Maximizing benefits in project selection: a hybrid approach

Charitable foundations and government programmes should endeavour to allocate their limited resources to best serve their constituents. Yet, mathematical programming techniques are rarely used despite overwhelming evidence of their superiority in selecting projects that yield higher levels of total benefits. We present a novel ‘hybrid selection model’ that combines binary linear programming and heuristic rank-based models applied to two case studies. The first case focuses on providing services to women and shows a hybrid model would have selected the top three ‘signature’ projects and maintained an above-average overall project benefit while securing a 180% improvement in the number of projects funded, a 66% improvement in the number of women served and a 132% improvement in the total benefit achieved. In the second case, we apply the hybrid approach to data from the US government’s largest forest preservation programme and demonstrate that the hybrid approach could allow the programme to select up to 11 top-scoring projects while still achieving a 97% gain in the total overall benefit compared to their traditional method. These case studies show that the hybrid approach has the potential to be applied in a variety of settings and improve how foundations and programmes achieve their goals.     

A fuzzy goal programming approach to analyse sustainable development goals of India

Energy policy, environmental planning and economic development play a key role in sustainable development. Sustainable development requires suitable and strategic policies satisfying multiple and conflicting objectives. Fuzzy goal programming (FGP) is a well-known approach in multi-criteria decision-making for its practical application. In this article, a FGP approach is proposed to analyse environmental, energy and sustainability goals of India by the year 2030 with reference to the key economic sectors of India. The presented model analyses the improvement opportunities, requirement of efforts and implementation of the sustainable development plans. Numerical illustration is also provided for validation and application of the proposed model.     

Linear Programming Models for the Measurement of Environmental Performance of Firms—Concepts and Empirical Results

I use linear programming models to define standardised, aggregate environmental performance indicators for firms. The best practice frontier obtained corresponds to decision making units showing the best environmental behaviour. Results are obtained with data from U.S. fossil fuel-fired electric utilities, starting from four alternative models, among which are three linear programming models that differ in the way they account for undesirable outputs (pollutants) and resources used as inputs. The results indicate important discrepancies in the rankings obtained by the four models. Rather than contradictory, these results are interpreted as giving different, complementary kinds of information, that should all be taken into account by public decision-makers.     

中原城市群生态环境保护的技术整合研究

通过生态工程技术来维护与提高城市群生态环境质量,是未来城市与区域发展的新理念,也是城市群可持续发展的基本支撑。在对中原城市群生态环境的现状问题分析的基础上,对中原城市群的生态环境的技术整合进行了研究。针对当前出现的生态环境问题,运用生态防护林地技术、自然保护区技术、生态园区设计技术、水源地保护技术、市区绿地系统规划技术、文物古迹保护技术、环境影响监测评价技术等进行整合,可为壮大中原城市群地区的生态资源与保障生态安全提供技术支撑。     

国家高新区提高了城市创新力吗

以我国2001-2016年240个地级市作为样本,基于国家高新区这一准自然实验,利用复旦大学产业发展研究中心发布的2017年《中国城市和产业创新力报告》中城市创新指数数据,基于双重差分(DID)法,评估其对城市创新力的影响。研究发现：①国家高新区设立可以显著提高所在城市创新能力,并呈现出随时间逐渐增强的动态发展趋势;②高新区的设立对城市创新能力提高的作用受所在地区初始要素禀赋影响,对初始要素禀赋具有比较优势的地区创新能力提升的促进效应更显著,对不同地区、不同等级、不同规模城市及不同城市群产生差异化影响。结论表明, 应充分结合各地区禀赋条件,将高新区更多设立在要素禀赋具有比较优势的地区。     

京津冀城市群经济联系的定量测度

依据城市群理论,城市之间的联系强弱是决定城市能否连接为一体、协同发展的重要因素。基于此,以2017年数据为背景,在综合利用城市职能强度模型、修正的空间引力模型和城市流模型的基础上,对京津冀城市群内部的空间联系进行实证研究,结果表明:北京和天津的"空吸"效应严重,资源要素向两市集聚,占据城市群绝对的核心位置;京津两市空间引力作用最大,远超群内其余城市,说明经济基础和空间距离是制约城市间联系紧密的关键要素;京津冀城市群整体外向型服务业发展良好,但是主要依赖传统服务业,高端服务业发展较弱;次级城市相对缺乏,整个京津冀城市群尚未形成良好的阶梯结构。最后,依据研究结果提出相应建议。